Slab flooring



Patented Feb. 10, 1942 UNITED STATES PAT ENT OFFICE SLAB FLOORING Theodore Barbato, White Plains, N. Y.

Application August 10, 1939, Serial No. 289,351

Claims.

The present invention relates to slab fioorings in which bays between girders are spanned by a system of ribs of reinforced concrete which serve as end supports for a system of hollow tile arches, each such arch consisting of a plurality of tiles bonded one to another by concrete fills, and the several arches being laterally juxtaposed to form a tile flooring which may be continuous except as interrupted by the girders, ribs and fills.

In the type of flooring with which'the invention is particularly concerned, the tiles are preferably set together in situ to form the arches; being supported by scaffolding at opposed edges of the tiles intermediate the concrete ribs, and being end-positioned on the reinforcing metal of the ribs before concrete is poured around such reinforcements; thus to provide a temporary support for the arches which will suflice to bear the load of all construction work thereafter to be performed thereon, including the load of any and all unset concrete which may be applied to the flooring.

In a flooring of this general character, an object of the invention is a reinforced concrete rib, for the purposes aforesaid, having as the reinforcement thereof a metal truss of such nature and so combined with the concrete as to result in a beam or rib having structural and economical advantages now to be set forth, and which have heretofore been unattainable.

A rib heretofore devised for use in a system such as mentioned consists of an I beam embedded in concrete. The lower flanges of such I beam afford excellent supports for tiles. and permit of some adjustability of the tiles with respect thereto, to allow for irregularities in construction work. Also, when the concrete is poured around the I beam between the same and the ends of the tiles, the tiles are bonded to the I beam right and left thereof. Such a rib is not, however, a reinforced concrete rib in the true sense of the term: and, because of existing standardizations of I beams, lacks some of the flexibility desired in meeting specifications which vary widely as to floor thickness and load capacity.

For such an I beam, I have substituted a truss of somewhat'similar cross section, but which consists of an openwork web made up of struts to which angle irons are Welded at top and bottom: and in such substitution the objections just noted in the use of I beams disappear, and a number of advantages are had which are not to be had in theuseof I beams.

Firstly: 'The concrete when poured or tamped around the truss will pass through the web between the struts thereof, and between the angle irons along those reaches thereof where no strut is present, and down around and under the angle irons: the struts serving to space laterally apart opposed angle irons for such flow of concrete therebetween. Instead, therefore, of the .concrete being formed in weaklyconnected masses right and left of the web, as in the case of an I beam, it here takes the form of a true monolith, reinforced at the bottom of the truss by angle irons which act as rods to take tensional strains, and from top to bottom by Web struts which take shearing stresses. The top angle bars act as compression membersin the carrying of construction loads prior to setting of the concrete: and in the completed floor add their compression strength to that of the concrete. The struts at their points of connection to the bars act as blocks, dogs, or lugs on the bars, holding the latter against longitudinal slip or shift in theconcrete.

Secondly: In the use, aforesaid, of angle irons, a reinforcing 'bar is had which, for a given selected cross section, or strength, presents a more extended and effective surface area for bonding thereof to the concrete than is presented by bars of round or other cross section, adaptable for the support of tiles thereon. As will hereinafter be noted, each angle iron bonds with the concrete at both the front and back faces of its vertical member, and at the under face of its horizontal member: so that the upper face of the horizontal member is not required for bonding with the concrete, and may be occupied by the ends of the tiles to any extent conformable to the adjustment of the latter with respect to the truss in the laying of the arches.

Thirdlyz' Angle irons, (as distinguished from I beams), may be had of almost any desired size, and may be as thick or thin as may be required for any given strength, rigidity, or depth of flooring,and the same applies to the truss webs. The truss structure, therefore, is of great flexibility as to design. This flexibility is such, for instance, as to open the Way for the use in the present invention of reinforcing bars of alloys having vastly greater tensile strength than ordinary steel,bars which as to weight and cross section for 'a given tensile strength may be less than of that of steel, but which nevertheless will require surface area, for bonding with the concrete, no less extensive than other bars. In the truss and the use thereof in the present invention full advantage may be taken of the great strength of such alloys as a means for reducing floor weight, because no matter how small the weight or total cross sectional area of an alloy reinforcement, it will, when properly designed as an angle iron, present all necessary surface area for bonding with the concrete.

It is obvious that since the truss is an assembly of parts welded or otherwise put together, the size, and relative size, and dimensions of top and bottom bars, and of the web, and the number and positioning of struts in the web, are freely variable, and any combination of truss elements may be selected to meet design requirements and to obtain economically a ribbed floor construction of maximum strength.

As hereinafter shown, the faces of the tiles, opposed to the trusses, are shaped to diverge or slant broadly away from the base of the truss to the floor surface, so as to permit of a concrete fill which when set will be a real concrete beam of substantial structural strength; and to the strength and rigidity of which is added that of the tiles themselves, by reason of the firm bonding and adhesion of the tiles to the concrete.

A feature of the invention is that the open construction of the trussed reinforcing member will permit conduits, pipes, etc., to pass therethrough, enabling such installations to be embedded in the slab, instead of being carried on the top of the truss. This feature enables the slab to be finished monolithically without addition of excessive and costly fills to cover these conduits, pipes, etc. This feature also tends to eliminate cracks in the finished floor construction, which might otherwise be caused by expansion and contraction of conduits and pipes installed too near the finished surface.

It will be understood that for floors of greater strength, and where space permits, a fill of concrete may be laid in a sheet over the trusses and tiles so as to monolithic with the fills around the trusses and therewith to form 'a 'Ifbeam concrete structure. It has also hereinbefore been mentioned that where tile is juxtaposed to tile in any arch, the opposed tile faces are bonded by concrete fills which constitute concrete blocks or beams running parallel to the trusses. These fills are made concurrently with the fills at the trusses and with any surfacing fill, so that where the latter is present it will form monolithic T beam structures with the fills between tiles.

The tiles where they oppose one another in an arch preferably have their faces so inclined upwardly and outwardly with respect to each other as not only to form a trough or mold of size suificient for the formation therein of a bonding block or beam of substantial structural strength, but so as to permit their lower opposed edges to be juxtaposed to close such trough or mold at the bottom thereof and to present an all-tile, continuous under surface or ceiling, to which plaster may be applied without chance of ultimate discoloration thereof such as commonly occurs where plaster is applied to ceiling surfaces of two or more different materials.

I am, of course, aware that trusses, more or less resembling the truss of the present invention, have been used in connection with floorings. In such prior use of trusses, however, the truss has not been in the plane of the floor slab and has not been a metal reinforcement for any concrete rib of such slab. It has been a truss on the top of which the slab as a whole was set.

The above and other objects and features of the invention W111 more fully appear in connection with the accompanying drawings, in which:

Fig. 1 is a top plan view of a section of flooring embodying the present invention: the concrete fills being incompletely applied thereto.

Fig. 2 is an enlarged cross sectional view taken on the line 22 of Fig. 1.

Fig. 3 is an enlarged cross sectional View taken on the line 3-3 of Fig. 1.

Fig. 4 is a full-size view, taken in cross section through the lower portion of one on the reinforced concrete beams and through the ends of two tiles supported thereon at opposite sides thereof.

Fig. 5 is a view in side elevation of one of the reinforcing trusses, showing a wall support for one end thereof and a girder support for the other end thereof, and showing also the manner in which trusses in different and successive bays may be united and made integral in effect by plates connecting the same over the girders.

Fig. 6 is a View in cross section on the line 6-6 of Fig. 5.

Fig. 7 is a view in cross section on the line of'Fig. 1, showing tiles which have their upper parts cut away to permit conduits to be laid thereon in the plane of the floor slab, and in such plane to be passed through the open-work of the trusses.

Referring to the drawings, there is shown in Fig. 5 one of the building walls l0, and one of the girders H which define the bays of the building structure. Spanning the bays and having end supports on the girders II, or, as in Fig. 5, on a girder H and wall H], are trusses l2, spaced apart a distance determined by the selected length of tile arch, see Fig. 2.

In Fig. 5 each truss I2 is shown as comprising a system or succession of struts [3. To the right and left faces of the struts, at the upper ends thereof, are welded or otherwise secured two angle irons l4 and I5, respectively. The horizontal flanges of these irons are shown as in the same plane, and as fiush with or slightly above the ends of the struts. To the right and left faces of the struts, at the lower ends thereof, are welded or otherwise secured two other angle irons Hi and 11, respectively. The horizontal flanges of angle irons l6 and I! lie in the same plane, fiush with or slightly below the lower ends of the struts l3.

The particular number and disposition of the struts l3 need not be that shown in Fig. 5, but may be varied according to circumstances. It has hereinbefore been stated that these struts have, among other functions, the function of re-- sisting shearing stresses. For this purpose they may be heavier or more numerous near the ends of the trusses than towards the center. Together, the struts form an open-work web conmeeting the angle irons, the truss as a whole having somewhat the cross section of an I beam. As hereinbefore explained, the size and weight of the angle irons, and the length and thickness of the arms thereof, and the height and thickness of the web, are all subject to variation at will to meet in the most economical manner the specifications or requirements as to strength, rigidity, weight, and depth of any flooring.

The shaded part of Fig. 1 defines one of the tile arches spanning the space between two of the trusses l2. This arch is shown in cross section in Figs. 2 and 3. It is shown as composed of two blocks or tile units I8 and I9, but if desired, the arches may .be composed of more than two tile units. As 'shownin Fig. 1, there is, between any two trusses I 2 asuccession of such arches, laterally juxtaposed, one to the other, to forrn a continuous flooring. v r

7 Before the arches are laid, there is erected a scaffolding comprising a board 20, see Fig. 2, positioned temporarily to support the-tiles at the sides thereof opposed to one another in the successive arches. Each of the tile units I8 and I9 abuts one of the trusses I2: and in that face of the tile which abuts a truss is a slot 2|. Into the slot 2 I inthe tile unit I8 protrudes the horizontal wing 2-2 of the angle iron I! at the left of atruss I2; and into the slot 2I in the tile unit I3 protrudes the horizontal wing 23, of the angle iron I6 atthe right of a truss I2. The arches are thus temporarily supported, centrally by the board 20, and at their ends by, the angle irons at the feet of the trusses I2 and asso supported, have their under surfaces 24 in horizontal alignment.

The opposed faces 25 and 26 of the tiles I8 and I9 in any arch are shown as inclined upwardly and outwardly with respect to each other from the bases to the tops of the tiles, to form molds or troughs 21 into which concrete may be poured or tamped which, when set, .will form blocks 28, see Fig. 3, of concrete permanently bonding together the several units of the arch, and giving to the arch the great compressive strength of such concrete block. When the troughs 21 in successive arches are in alignment, the blocks 28 will assume the form of concrete beams or ribs extending crosswise of the arches intermediate and parallel to the trusses I2, thus further increasing the compressive strength of the floor. To assure the creation of blocks or ribs of true concrete, the troughs 21 should be of width and depth sufficient to allow for absorption of water from the mix by the tiles.

The shape and setting 'of the opposed faces 25 and 26 of the tiles 'I8 and I9 is such as to close the troughs 2'! at the bottom, except for a clearance 29 at the base of the tiles. Similar clearances 30 are shown between the ends of the tiles below the trusses I2. These clearances are too small to allow leakage of concrete therethrough. They are so small that the under surfaces 25 of the tiles form an all-tile, or one material, continuous ceiling surface: thus precluding the discoloration of plaster thereon, arising from variations in the effects of light passing through plaster laid over materials of different densities and nature.

The clearances 29 and 30 have several important purposes. Firstly, they allow for any slight irregularities in the placement of the trusses I2. Secondly, they permit the tile units, by reason of the slots 2I therein, to be hooked onto the wings 22 and 23 of the angle irons IB'and IT at the feet of the trusses, and thereafter to be swung down upon the boards 20. Thirdly, they serve as means whereby to key plaster or other ceiling to the under face of the flooring.

For economy in construction, it is desirable that a minimum of scaffolding be required, and that the same be removable with as little delay as possible. Due, however, to the fact that concrete may be laid much faster than it will set, the maintenance of an extensive scaffolding for construction loads has ordinarily been necessary. The situation is otherwise'with the present invention. Here the boards of the scaffolding are no part of any form within whichto cast the concrete: the tiles of themselves are the complete forms: and, as above pointed out, together present an all-tile bottom surface, continuous except for joints29 and 30 which are substantially concrete tight. The trusses support the tiles at the ends ofthe arches: and the only scaffolding required is one to support the tiles along the lines of the boards 20.

This scaffolding may, of course be left in place untilthe concrete has set, in which event it would have to be a more or less extensive scaffolding, Having served its initial purpose as a platform on which to lay the tiles, it may, however, be rep1ace'd,,so far as the carrying of construction loads is concerned, by Wedges 3|, see Figs. 1 and 2, driven into the troughs 21, to lock the tiles one to another, and to make the arches self-sustaining. Asmall scaffolding, progressively movable with:the driving of the wedges, will therefore here suflice for the laying of an entire floor.

In 1 connection with the use, aforesaid, of wedges 3|, the clearances 29 and 30 are seen to have a further .useful purpose. They allow for a spreading apart of the tiles I8 and I9 by the wedges, sothat the tiles, at the inner ends of their slots 2|, may be jammed tightly against the ends of those wings of the angle irons IB and I! on which the ends of the arches are supported. Theseslots 2| are shown as having their lower walls inclined downwardly as at 32, not only toallow for the swing, aforesaid, of the tiles, in hooking them to the trusses and positioning them upon the boards 20, but to provide for a concrete fill, hereinafter mentioned, below the bars lfiz and I1.

Upon reference to Figs. 2 and 3, it will be noted that the .tiles are so shaped that their opposed faces 33 and 34 at the trusses I2 diverge broadly upward from the angle irons at the feet of the trusses to the tops of the tiles. This provides for a fill of concrete between the tiles, sufiicient, with the trusses I2, to form a true reinforced concrete beam or rib for the flooring, bonding together the arches on opposite sides of the trusses.

' This shaping of the tiles also assures clear passage for the concrete to the truss and tile surfaces to be bonded thereby.

Referring to Fig. 5, it will be noted that the end struts 35, by which the trusses are supported onthe lower flanges 36 of the'girders II, are extended below the bars I3 and I7. Where trusses of an end bay are to rest upon a wall I0, they may be provided with vertical strut members 31 having foot plates 38. The members 31, like the end struts 35, will ordinarily be heavier, that is to say, broader (see Fig. 5) than the other struts I3, but of the same thickness: so that all truss struts may lie in a common plane between, and welded or otherwise secured to, opposed angle'irons, I4 and I5 at the top of the truss, and I6 and I? at the bottom thereof. The trusses in one bay may b made continuous with those in a next succeeding bay by means of plates 39, see Fig. 5. These plates extend from one truss to another across the top flanges so of the intermediate girder II. Opposite ends of the plates are welded or otherwise secured to the trusses: and, for greater rigidity, the plates may also be welded to the top faces of the girders, intermediate the trusses which they connect.

It has been stated that the open work of the truss webs I3 permits conduits, pipes, etc. to pass therethrough, so that the latter need not be laid at the top of the flooring. For this purpose, see Figs. land 7, -those tiles IBand I9 which are to be crossed by the conduits may be cut down to the plane of the top of the webs l8 and IQ of the tiles, and the conduits laid on such webs l8 and 19'. In Fig. 7 such a conduit 60 is shown extending through the open-work of the truss webs I3 and over the tile webs l8 and I9.

The flooring elements having been set together as above described, and as shown in Figs. 1 and 2, the structure is ready for the concrete fills. The fill at the trusses 12 will pass down around the trusses, through the open-work thereof, and into contact with all surfaces of the struts I3, 35 and 31 not covered by the angle irons l4, l5, l6 and H. Along those reaches of the lower angle irons l6 and I1 between such points 4| thereof, where the struts are welded to the bars, the concrete will flow between the opposed and spaced vertical faces, 42 and 43 respectively, of the upright wings 44 and 45 of angle irons l6 and ll, and into the space formed by the notches 2| in the tiles, below the bars [6 and H. In so doing, it will contact the inclined tile surfaces 32 of the notches or slots 2|, and the entire under surfaces of the horizontal wings 22 and 23 of bars l6 and llz thus bonding tiles and bars firmly together over these surfaces, and over the entire opposed faces 42 and 43 of the lower bars.

To right and left of the truss, the fill will contact the entire faces 33 and 34 of the tiles, and the outside faces 46 and 41 of the vertical wings 4 and 45 of the lower angle bars. It will also contact whatever of the upper surfaces of the horizontal wings 22 and 23 of the bars is not occupiecl by the tiles l8 and I9. At the top of the truss, the concrete will flow between the angle bars i l and I along such reaches thereof as lie between points 38 where the bars are welded to th struts I3, 35 and 31, and will bond to the opposed vertical faces 49 and 50 of the upright wings of these bars I4 and I5. It will also bond with the upper bars over the outer vertical surfaces of the upright wings of the bars I4 and i5: and over the entire upper and lower surfaces of the horizontal wings of the bars [4 and 15.

Due to the passage of the concrete through the open-Work of the truss web, the concrete right and left of the truss will form a monolithic mass which, with the truss, will comprise a reinforced concrete beam securely bonded to the tiles in all possible planes of stress by reason of the concrete-contacting surfaces just mentioned.

t the ends of the trusses, the concrete will contact all surfaces of the struts 35 and 31, not crossed by the angle irons, and will contact all surfaces of the web and flanges of the girders ll, except such surfaces thereof as are covered by the truss-uniting plates 39 or foot plates 5| for struts 35, and it will cover the tops of any such plates 39 and 5|, and will bond with the under surfaces of plates 39 where they are not crossed by the top faces of the girders.

The troughs 27 between th opposed tiles in the arches are filled progressively with the fillings around the trusses, thus bonding such tiles firmly together to make rigid unitary structures of th arches. If wedges 3| have been substituted for the boards 2!) to carry the construction loads, they are left in place, and the fill poured or tamped over, around and under the same.

As hereinbefore stated, the fills at the trusses i2 and in the troughs 21 may be brought flush with the tops of th tiles, and the flooring finished in that condition, in which event the flooring will be a tile flooring having ribbings or beams of concrete extending therealong at the trusses l2 and troughs 21. On the other hand, as shown at 52 in Figs. 1 and 3, the filling may be continued as a substantial layer of concrete over the tops of tiles and trusses: and such layer 52 may be laid simultaneously with the fills at trusses l2 and troughs 21, to be monolithic therewith, in which event there will be a system of integrally and monolithically connected concrete beams, of T beam cross-section, interwoven with the tile arches to form a flooring of extraordinary strength for any given weight and thickness. Where any tiles are cut down to their horizontal webs l8 and IQ for positioning of conduits thereon, the conduits are laid before the fills are made, and concrete is filled in around the same to th level of the top of the rest of the floor, as shown at 6| in Fig. '7.

As heretofore stated, in the reinforced beam of the present invention, the angle irons l6 and l! are bars properly positioned to take the tensional strains. As shown in Fig. 6, the struts l3, to which bars I6 and H are welded, are laterally ofiset from the bars in such a manner as to act as blocks, lugs or dogs resisting any pull on the bars which might tend to displace the same longitudinally in the concrete. The struts l3 resist shearing stresses. The upper angle irons l4 and 15 act as compression members for construction loads, and after the concrete fills have set, continue to act as compression members in reinforcement of the concrete.

I claim:

1. A composite concrete and tile floor slab, comprising a system of multiple-tile, permanentload sustaining arches, and a system of reinforced concrete ribs; the arches being spaced apart, end from end, in rows, each row constituting a succession of spans, and the concrete ribs being fills which lie between and which bond one to another the opposed ends of the arches in the several rows; the reinforcements for the concrete ribs comprising open-work webs set upright in the plane of the slab, and bars secured to and projecting laterally from the webs serving as seats for the ends of the arches, said bars being imbedded in the concrete above the base of the fills for service as true tension members therein.

2. A composite concrete and tile floor slab, comprising a system of multiple-tile, permanentload sustaining arches, and a system of reinforced concrete ribs; the arches being spaced apart, end from end, in rows, each row constituting a succession of spans, and the concrete ribs being fills which lie between and which bond one to another the opposed ends of the arches in the several rows; the reinforcements for the concrete ribs comprising open-work webs set upright in the Plane of the slab, and angle-irons secured to and projecting laterally from the webs serving as seats for the ends of the arches, said angle-irons being imbedded in the concrete above the base of the fills for service as true tension members therein.

3. A composite concrete and tile floor slab, comprising a system of multiple-tile, permanentload sustaining arches, and a system of reinforced concrete ribs; the arches being spaced apart, end from end, in rows, each row constituting a succession of spans, and the concrete ribs being fills which lie between and which bond one to another the opposed ends of the arches in the several rows; the reinforcements for the concrete ribs comprising open-work webs set upright in the plane of the slab, and bars secured to and projecting laterally from the webs serving as seats for the ends of the arches, said bars being imbedded in the concrete above the base of the fills for service as true tension members therein; the several tiles which make up each multipletile arch being of shape and size to permit of independent manipulation thereof for seating the tiles upon the bars, after the reinforcements have been positioned, and without movement of the tiles end-wise of the bars.

4. A composite concrete and tile fioor slab, comprising a system of multiple-tile, permanentload sustaining arches, and a system of reinforced concrete ribs; the arches being spaced apart, end from end, in rows, each row constituting a succession of spans, and the concrete ribs being fills which lie between and which bond one to another the opposed ends of the arches in the several rows; the reinforcements for the concrete ribs comprising open-work webs set upright in the plane of the slab, and bars secured to and projecting laterally from the webs serving as seats for the ends of the arches, said bars being imbedded in the concrete above the base of the fills for service as true tension members therein; the several tiles which make up each multipletile arch being of shape and size to permit of independent manipulation thereof for seating the tiles upon the bars, after the reinforcements have been positioned, and without movement of the tiles end-Wise of the bars, and concrete fills between the several tiles of a multiple-tile arch for locking the same against displacement.

5. A composite concrete and tile floor slab, comprising a system of multiple-tile, permanentload sustaining arches, and a system of reinforced concrete ribs, the arches being spaced apart, end from end, in rows, each row constituting a succession of spans, and the concrete ribs being fills which lie between and which bond one to another the opposed ends of the arches in the several rows; the reinforcements for the concrete ribs comprising open-work webs set upright in the plane of the slab, and bars secured to and projecting laterally from the webs serving as seats for the ends of the arches, said bars being imbedded in the concrete above the base of the fills for service as true tension members therein; the several tiles which make up each multipletile arch being of shape and size to permit of independent manipulation thereof for seating the tiles upon the bars, after the reinforcements have been positioned, and without movement of the tiles end-wise of the bars, and concrete fills between the several tiles of a multiple-tile arch for locking the same against displacement, said last-mentioned fills being permanent-load sustaining concrete ribs.

THEODORE BARBATO. 

